Improvement in cooking-stoves



J. H. SHEAR.

Cooking Stove.

Patented Sept. 7, 1869.

tinned grates against clam.

JA 0 0 B H. s H E A R, 0 r A L B A NZ,

Letters Patent No. 94,658, dated September 7 1869.

IMPROVEMENT IN COOKING-STOVES The Schedule referred to in these LettersPatent and making part of the same.

and county of Albany, and State of New York, have invented a new anduseful Improvement in Cooking- Stoves; and I hereby declare thefollowing to be a full and exact description of said improvement, refer:

'ence being bad to the accompanying drawings, and to the letters ofreference marked thereon, the same letter always referring to the samepart of the stove.

The improvement has reference to such an organization and arrangement aswill tend to modify the per cent. of combustion within the fire-pot,within any given time, to any desirable degree, and also to equalize therate of combustion in every part of the firepot, and upon the grate,producing a uniform rate of combustion in or on every part of the grate.

My said improvementconsists in so introducing the air for sustainingcombustion into the fire-chamber as that the coal at the extremities ofthe grate shall burn equally well with that upon the centre of thegrate. To do this, compensation must be made for the excess of radiationgoing on at the ends of the grate, for it is well known, in thepractical operation of stoves, that the tendency is for the fire to diefirst at the end of the grate or fire-pot, where the radiation is thegreatest.

This being the case, provision for such compensation must be made inwell-organized stoves having an elongated grate or fire-pot.

Figure 1, in the accompanying drawings, is' a representation of a stovehaving provision made therein for such compensation. V

The door of the stove a a, in fig. 1, is a compoundchambereddoor,consisting of two chambers, front and rear, connected with each otherby, means of flues or openings in the upper sides of the partition,separating them, so located, in respect to each other; as that there isa closed space between them, as seen in Figure 4, c c.

The second chamber is formed by means of a plate, d d, Figure 5, soattached to the inside of the door as that the openings in to the stoveand under the grate shall' be at the ends and on the lower side of suchchamber, as seen in Figure 2, d d.

The manner in which the air enters these chambers is represented in fig.1, at the openings a It is to be observed that this compound-chambereddoor is so constructed that the air enters on the lower side and nearthe ends of the first or front chamber. Thence it arises to the top ofthe chamber, and enters the second chamber through the openings 0 c infig. 4. It then descends to the bottdm'of the second or rear chamber,and enters the stove through the openings d d at the points 9 g, fig. 2,and thus furnishes air in a proper condition and location to aidcombustion in the ends of the grate.

These chambers are made to exclude-the passage of air at'or near themiddle of the chamber, for the purpose of compelling all the air passingthe chambers to pass to the ends'of the grate and fire-pot, to produceincreased combustion, there to compensate 'for the increased radiationin that part of the firepot.

To aid further in the matter of compensation, I introduce warm airwithin the fire-pot, near the ends of the same, by means of fines b b,as seen in 'figs. l and 2. Air is supplied to these flues b I) throughthe openiugs at k in the top of the stove, fig. 1.

It must be observed that the air aiding combustion at the ends of thegrate is so introducedfor that purpose that it becomes more or lessheated while in its passage to the grate by taking up caloric which isbeing radiated, and by these means it returns, for aid in the support ofthe moderate combustion desired in the firepot, caloric, whichwould-otherwise pass off and be dissipated or lost for such purpose.

Connected with this improvement, and for united action with the same,are the dampers e and f in the exit-pipe, fig. 1.

I have demonstrated, by long 4 continued experiments, that theimprovement is complete by means of using these dampers, andparticularly by the use of the damper-f.

The improvement can be worked very well by the use of the damper f only,although it is more perfect by the use of both c and f.

I have likewise demonstrated that the improvement is not completewithout the united action of one or both these-dampers.

When I wish to keep up a very moderate fire upon the entire length ofthe grate, for any considerable time, as from eveningnutil morning, orfrom morning until morning again, without attending to the fire in themeantime, I see that the fuel on the grate is in well condition forignition, and properly supplied.

I then close my compound-chambered door a a, fig. 1,

opening the lower draughts therein, a a.

I also open the draught-damper e and close the damper f in theexit-pipe.

By thus operating my stove, I find I can keep the coal upon the grate,"from end to end, alive with fire from eighteen to twenty-seven hourswithout further attention, and consuming in the meantime only abouttwenty to twenty-five pounds of coal; but by neglect ing the arrangementas above described, the tire uniformly goes out before morning.

I have repeated these experiments constantly for many weeks with uniformresults, and have thusdemonst'rated the actuality and value of my saidimprovements, and that the said chambers, fines, and dampers co-operateto produce the desired result.

I have also experimented, during the time above mentioned, for thepurpose of testing the value of the improvement, which compels the airto pass into the fire-pot from the endsof the chambers in the door,instead of passing in through a continuous opening 'from the chamber,that is, an opening along the bot-- tom, and from end to end of thechamber, and the result has been uniform. that, when I compelled the airto enter the fire-pot from the lateral end flue only, the combustion onthe ends of the grate has v been kept up, but when I extended theflue-opening entirely across the chamber, the fire at the ends has dieddown; therefore, I adopted the division of the fine-openings in thechamber of my'door as a part of my said'improrement; and when a chamberis located elsewhere than in the door, a like arrangement,.with a viewof affecting combustion in the ends of the grate, will also include thisfeature of' my said improvement.

Haring thus fully described my said invention and improvement,

I will now proceed to state what I claim, and desire to secure byLetters Patent.

In a cooking-stove, of the general construction and arrangementdescribed, I claim the chambered door, grate, flues, dampers e and f,and exit-pipe, under the combination substantially as represented.

JACOB H. SHEAR.

Witnesses:

J OEL- TIFFANY DANIEL KETCHUM.

